[ltt-dev] [rp] [PATCH RFC urcu 2/4] Map symbols to allow multiple RCU flavors to be used in one binary
Paul E. McKenney
paulmck at linux.vnet.ibm.com
Wed Apr 13 20:10:51 EDT 2011
On Wed, Apr 13, 2011 at 05:24:49PM -0400, Mathieu Desnoyers wrote:
> * Paul E. McKenney (paulmck at linux.vnet.ibm.com) wrote:
> > Probably need similar mapping for rcu_defer(). Definitely need
> > backwards-compatibility mapping for programs compiled against
> > old versions of the library.
>
> Either that or we bump the version to 0.6.x ? Otherwise, we'll have to
> keep tons of .so around just to do the compatibility layer for older
> linking behavior.
>
> Thoughts ?
I think that bumping the version makes a lot of sense -- people can always
download the old version. Good point!!!
Thanx, Paul
> Mathieu
>
> >
> > Signed-off-by: Paul E. McKenney <paulmck at linux.vnet.ibm.com>
> > ---
> > Makefile.am | 3 +-
> > tests/Makefile.am | 33 ++--
> > tests/rcutorture.h | 1 -
> > tests/urcutorture.c | 13 +-
> > urcu-bp-map.h | 61 +++++
> > urcu-bp.c | 4 +
> > urcu-bp.h | 8 +-
> > urcu-call-rcu-impl.h | 618 +++++++++++++++++++++++++++++++++++++++++++++++++
> > urcu-call-rcu.c | 620 --------------------------------------------------
> > urcu-map.h | 117 ++++++++++
> > urcu-qsbr-map.h | 63 +++++
> > urcu-qsbr.c | 36 ++--
> > urcu-qsbr.h | 18 +-
> > urcu.c | 5 +
> > urcu.h | 20 ++-
> > 15 files changed, 945 insertions(+), 675 deletions(-)
> > create mode 100644 urcu-bp-map.h
> > create mode 100644 urcu-call-rcu-impl.h
> > delete mode 100644 urcu-call-rcu.c
> > create mode 100644 urcu-map.h
> > create mode 100644 urcu-qsbr-map.h
> >
> > diff --git a/Makefile.am b/Makefile.am
> > index 7956e7e..ef3bfef 100644
> > --- a/Makefile.am
> > +++ b/Makefile.am
> > @@ -30,7 +30,7 @@ COMPAT+=compat_futex.c
> > endif
> >
> > lib_LTLIBRARIES = liburcu.la liburcu-qsbr.la liburcu-mb.la liburcu-signal.la \
> > - liburcu-bp.la liburcu-defer.la liburcu-call.la \
> > + liburcu-bp.la liburcu-defer.la \
> > libwfqueue.la libwfstack.la librculfqueue.la librculfstack.la
> >
> > liburcu_la_SOURCES = urcu.c urcu-pointer.c $(COMPAT)
> > @@ -45,7 +45,6 @@ liburcu_signal_la_CFLAGS = -DRCU_SIGNAL
> >
> > liburcu_bp_la_SOURCES = urcu-bp.c urcu-pointer.c $(COMPAT)
> >
> > -liburcu_call_la_SOURCES = urcu-call-rcu.c $(COMPAT)
> > liburcu_defer_la_SOURCES = urcu-defer.c $(COMPAT)
> >
> > libwfqueue_la_SOURCES = wfqueue.c $(COMPAT)
> > diff --git a/tests/Makefile.am b/tests/Makefile.am
> > index 3c025a4..8dacb11 100644
> > --- a/tests/Makefile.am
> > +++ b/tests/Makefile.am
> > @@ -28,21 +28,20 @@ if COMPAT_FUTEX
> > COMPAT+=$(top_srcdir)/compat_futex.c
> > endif
> >
> > -URCU=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > -URCU_QSBR=$(top_srcdir)/urcu-qsbr.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > +URCU=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > +URCU_QSBR=$(top_srcdir)/urcu-qsbr.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > # URCU_MB uses urcu.c but -DRCU_MB must be defined
> > -URCU_MB=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > +URCU_MB=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > # URCU_SIGNAL uses urcu.c but -DRCU_SIGNAL must be defined
> > -URCU_SIGNAL=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > -URCU_BP=$(top_srcdir)/urcu-bp.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > -URCU_DEFER=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-defer.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/urcu-call-rcu.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > +URCU_SIGNAL=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > +URCU_BP=$(top_srcdir)/urcu-bp.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
> > +URCU_DEFER=$(top_srcdir)/urcu.c $(top_srcdir)/urcu-defer.c $(top_srcdir)/urcu-pointer.c $(top_srcdir)/wfqueue.c $(COMPAT)
> >
> > URCU_LIB=$(top_builddir)/liburcu.la
> > URCU_QSBR_LIB=$(top_builddir)/liburcu-qsbr.la
> > URCU_MB_LIB=$(top_builddir)/liburcu-mb.la
> > URCU_SIGNAL_LIB=$(top_builddir)/liburcu-signal.la
> > URCU_BP_LIB=$(top_builddir)/liburcu-bp.la
> > -URCU_CALL_LIB=$(top_builddir)/liburcu-call.la
> > WFQUEUE_LIB=$(top_builddir)/libwfqueue.la
> > WFSTACK_LIB=$(top_builddir)/libwfstack.la
> > RCULFQUEUE_LIB=$(top_builddir)/librculfqueue.la
> > @@ -95,24 +94,24 @@ test_perthreadlock_SOURCES = test_perthreadlock.c $(URCU_SIGNAL)
> >
> >
> > rcutorture_urcu_SOURCES = urcutorture.c
> > -rcutorture_urcu_CFLAGS = -DTORTURE_URCU $(AM_CFLAGS)
> > -rcutorture_urcu_LDADD = $(URCU) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
> > +rcutorture_urcu_CFLAGS = -DRCU_MEMBARRIER $(AM_CFLAGS)
> > +rcutorture_urcu_LDADD = $(URCU) $(WFQUEUE_LIB)
> >
> > rcutorture_urcu_mb_SOURCES = urcutorture.c
> > -rcutorture_urcu_mb_CFLAGS = -DTORTURE_URCU_MB $(AM_CFLAGS)
> > -rcutorture_urcu_mb_LDADD = $(URCU_MB_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
> > +rcutorture_urcu_mb_CFLAGS = -DRCU_MB $(AM_CFLAGS)
> > +rcutorture_urcu_mb_LDADD = $(URCU_MB_LIB) $(WFQUEUE_LIB)
> >
> > rcutorture_qsbr_SOURCES = urcutorture.c
> > -rcutorture_qsbr_CFLAGS = -DTORTURE_QSBR $(AM_CFLAGS)
> > -rcutorture_qsbr_LDADD = $(URCU_QSBR_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
> > +rcutorture_qsbr_CFLAGS = -DRCU_QSBR $(AM_CFLAGS)
> > +rcutorture_qsbr_LDADD = $(URCU_QSBR_LIB) $(WFQUEUE_LIB)
> >
> > rcutorture_urcu_signal_SOURCES = urcutorture.c
> > -rcutorture_urcu_signal_CFLAGS = -DTORTURE_URCU_SIGNAL $(AM_CFLAGS)
> > -rcutorture_urcu_signal_LDADD = $(URCU_SIGNAL_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
> > +rcutorture_urcu_signal_CFLAGS = -DRCU_SIGNAL $(AM_CFLAGS)
> > +rcutorture_urcu_signal_LDADD = $(URCU_SIGNAL_LIB) $(WFQUEUE_LIB)
> >
> > rcutorture_urcu_bp_SOURCES = urcutorture.c
> > -rcutorture_urcu_bp_CFLAGS = -DTORTURE_URCU_BP $(AM_CFLAGS)
> > -rcutorture_urcu_bp_LDADD = $(URCU_BP_LIB) $(URCU_CALL_LIB) $(WFQUEUE_LIB)
> > +rcutorture_urcu_bp_CFLAGS = -DRCU_BP $(AM_CFLAGS)
> > +rcutorture_urcu_bp_LDADD = $(URCU_BP_LIB) $(WFQUEUE_LIB)
> >
> > test_mutex_SOURCES = test_mutex.c $(URCU)
> >
> > diff --git a/tests/rcutorture.h b/tests/rcutorture.h
> > index 66fdd7f..aba74b0 100644
> > --- a/tests/rcutorture.h
> > +++ b/tests/rcutorture.h
> > @@ -66,7 +66,6 @@
> > */
> >
> > #include <stdlib.h>
> > -#include "../urcu-call-rcu.h"
> >
> > DEFINE_PER_THREAD(long long, n_reads_pt);
> > DEFINE_PER_THREAD(long long, n_updates_pt);
> > diff --git a/tests/urcutorture.c b/tests/urcutorture.c
> > index 63fa386..a098d87 100644
> > --- a/tests/urcutorture.c
> > +++ b/tests/urcutorture.c
> > @@ -8,22 +8,19 @@
> > #include "api.h"
> > #define _LGPL_SOURCE
> >
> > -#ifdef TORTURE_RCU_MEMBARRIER
> > -#define RCU_MEMBARRIER
> > +#ifdef RCU_MEMBARRIER
> > #include <urcu.h>
> > #endif
> > -#ifdef TORTURE_URCU_SIGNAL
> > -#define RCU_SIGNAL
> > +#ifdef RCU_SIGNAL
> > #include <urcu.h>
> > #endif
> > -#ifdef TORTURE_URCU_MB
> > -#define RCU_MB
> > +#ifdef RCU_MB
> > #include <urcu.h>
> > #endif
> > -#ifdef TORTURE_QSBR
> > +#ifdef RCU_QSBR
> > #include <urcu-qsbr.h>
> > #endif
> > -#ifdef TORTURE_URCU_BP
> > +#ifdef RCU_BP
> > #include <urcu-bp.h>
> > #endif
> >
> > diff --git a/urcu-bp-map.h b/urcu-bp-map.h
> > new file mode 100644
> > index 0000000..6321802
> > --- /dev/null
> > +++ b/urcu-bp-map.h
> > @@ -0,0 +1,61 @@
> > +#ifndef _URCU_BP_MAP_H
> > +#define _URCU_BP_MAP_H
> > +
> > +/*
> > + * urcu-map.h
> > + *
> > + * Userspace RCU header -- name mapping to allow multiple flavors to be
> > + * used in the same executable.
> > + *
> > + * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> > + * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
> > + *
> > + * LGPL-compatible code should include this header with :
> > + *
> > + * #define _LGPL_SOURCE
> > + * #include <urcu.h>
> > + *
> > + * This library is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU Lesser General Public
> > + * License as published by the Free Software Foundation; either
> > + * version 2.1 of the License, or (at your option) any later version.
> > + *
> > + * This library is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * Lesser General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU Lesser General Public
> > + * License along with this library; if not, write to the Free Software
> > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> > + *
> > + * IBM's contributions to this file may be relicensed under LGPLv2 or later.
> > + */
> > +
> > +/* Mapping macros to allow multiple flavors in a single binary. */
> > +
> > +#define rcu_read_lock rcu_read_lock_bp
> > +#define _rcu_read_lock _rcu_read_lock_bp
> > +#define rcu_read_unlock rcu_read_unlock_bp
> > +#define _rcu_read_unlock _rcu_read_unlock_bp
> > +#define rcu_register_thread rcu_register_thread_bp
> > +#define rcu_unregister_thread rcu_unregister_thread_bp
> > +#define rcu_init rcu_init_bp
> > +#define rcu_exit rcu_exit_bp
> > +#define synchronize_rcu synchronize_rcu_bp
> > +#define rcu_reader rcu_reader_bp
> > +#define rcu_gp_ctr rcu_gp_ctr_bp
> > +
> > +#define get_cpu_call_rcu_data get_cpu_call_rcu_data_bp
> > +#define get_call_rcu_thread get_call_rcu_thread_bp
> > +#define create_call_rcu_data create_call_rcu_data_bp
> > +#define set_cpu_call_rcu_data set_cpu_call_rcu_data_bp
> > +#define get_default_call_rcu_data get_default_call_rcu_data_bp
> > +#define get_call_rcu_data get_call_rcu_data_bp
> > +#define get_thread_call_rcu_data get_thread_call_rcu_data_bp
> > +#define set_thread_call_rcu_data set_thread_call_rcu_data_bp
> > +#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_bp
> > +#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_bp
> > +#define call_rcu call_rcu_bp
> > +
> > +#endif /* _URCU_BP_MAP_H */
> > diff --git a/urcu-bp.c b/urcu-bp.c
> > index 04bb675..5474f9f 100644
> > --- a/urcu-bp.c
> > +++ b/urcu-bp.c
> > @@ -35,6 +35,8 @@
> > #include <unistd.h>
> > #include <sys/mman.h>
> >
> > +#include "urcu-bp-map.h"
> > +
> > #include "urcu-bp-static.h"
> > /* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
> > #include "urcu-bp.h"
> > @@ -375,3 +377,5 @@ void rcu_bp_after_fork_child(void)
> > ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
> > assert(!ret);
> > }
> > +
> > +#include "urcu-call-rcu-impl.h"
> > diff --git a/urcu-bp.h b/urcu-bp.h
> > index d92fbd1..fdf885c 100644
> > --- a/urcu-bp.h
> > +++ b/urcu-bp.h
> > @@ -46,6 +46,8 @@
> > extern "C" {
> > #endif
> >
> > +#include "urcu-bp-map.h"
> > +
> > /*
> > * Important !
> > *
> > @@ -69,8 +71,8 @@ extern "C" {
> > *
> > * Mark the beginning and end of a read-side critical section.
> > */
> > -#define rcu_read_lock() _rcu_read_lock()
> > -#define rcu_read_unlock() _rcu_read_unlock()
> > +#define rcu_read_lock_bp() _rcu_read_lock()
> > +#define rcu_read_unlock_bp() _rcu_read_unlock()
> >
> > #else /* !_LGPL_SOURCE */
> >
> > @@ -115,4 +117,6 @@ static inline void rcu_init(void)
> > }
> > #endif
> >
> > +#include "urcu-call-rcu.h"
> > +
> > #endif /* _URCU_BP_H */
> > diff --git a/urcu-call-rcu-impl.h b/urcu-call-rcu-impl.h
> > new file mode 100644
> > index 0000000..68dbbdd
> > --- /dev/null
> > +++ b/urcu-call-rcu-impl.h
> > @@ -0,0 +1,618 @@
> > +/*
> > + * urcu-call-rcu.c
> > + *
> > + * Userspace RCU library - batch memory reclamation with kernel API
> > + *
> > + * Copyright (c) 2010 Paul E. McKenney <paulmck at linux.vnet.ibm.com>
> > + *
> > + * This library is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU Lesser General Public
> > + * License as published by the Free Software Foundation; either
> > + * version 2.1 of the License, or (at your option) any later version.
> > + *
> > + * This library is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * Lesser General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU Lesser General Public
> > + * License along with this library; if not, write to the Free Software
> > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> > + */
> > +
> > +#include <stdio.h>
> > +#include <pthread.h>
> > +#include <signal.h>
> > +#include <assert.h>
> > +#include <stdlib.h>
> > +#include <string.h>
> > +#include <errno.h>
> > +#include <poll.h>
> > +#include <sys/time.h>
> > +#include <syscall.h>
> > +#include <unistd.h>
> > +
> > +#include "config.h"
> > +#include "urcu/wfqueue.h"
> > +#include "urcu-call-rcu.h"
> > +#include "urcu-pointer.h"
> > +#include "urcu/list.h"
> > +
> > +/* Data structure that identifies a call_rcu thread. */
> > +
> > +struct call_rcu_data {
> > + struct cds_wfq_queue cbs;
> > + unsigned long flags;
> > + pthread_mutex_t mtx;
> > + pthread_cond_t cond;
> > + unsigned long qlen;
> > + pthread_t tid;
> > + struct cds_list_head list;
> > +} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
> > +
> > +/*
> > + * List of all call_rcu_data structures to keep valgrind happy.
> > + * Protected by call_rcu_mutex.
> > + */
> > +
> > +CDS_LIST_HEAD(call_rcu_data_list);
> > +
> > +/* Link a thread using call_rcu() to its call_rcu thread. */
> > +
> > +static __thread struct call_rcu_data *thread_call_rcu_data;
> > +
> > +/* Guard call_rcu thread creation. */
> > +
> > +static pthread_mutex_t call_rcu_mutex = PTHREAD_MUTEX_INITIALIZER;
> > +
> > +/* If a given thread does not have its own call_rcu thread, this is default. */
> > +
> > +static struct call_rcu_data *default_call_rcu_data;
> > +
> > +/*
> > + * If the sched_getcpu() and sysconf(_SC_NPROCESSORS_CONF) calls are
> > + * available, then we can have call_rcu threads assigned to individual
> > + * CPUs rather than only to specific threads.
> > + */
> > +
> > +#if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF)
> > +
> > +/*
> > + * Pointer to array of pointers to per-CPU call_rcu_data structures
> > + * and # CPUs.
> > + */
> > +
> > +static struct call_rcu_data **per_cpu_call_rcu_data;
> > +static long maxcpus;
> > +
> > +/* Allocate the array if it has not already been allocated. */
> > +
> > +static void alloc_cpu_call_rcu_data(void)
> > +{
> > + struct call_rcu_data **p;
> > + static int warned = 0;
> > +
> > + if (maxcpus != 0)
> > + return;
> > + maxcpus = sysconf(_SC_NPROCESSORS_CONF);
> > + if (maxcpus <= 0) {
> > + return;
> > + }
> > + p = malloc(maxcpus * sizeof(*per_cpu_call_rcu_data));
> > + if (p != NULL) {
> > + memset(p, '\0', maxcpus * sizeof(*per_cpu_call_rcu_data));
> > + per_cpu_call_rcu_data = p;
> > + } else {
> > + if (!warned) {
> > + fprintf(stderr, "[error] liburcu: unable to allocate per-CPU pointer array\n");
> > + }
> > + warned = 1;
> > + }
> > +}
> > +
> > +#else /* #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
> > +
> > +static const struct call_rcu_data **per_cpu_call_rcu_data = NULL;
> > +static const long maxcpus = -1;
> > +
> > +static void alloc_cpu_call_rcu_data(void)
> > +{
> > +}
> > +
> > +static int sched_getcpu(void)
> > +{
> > + return -1;
> > +}
> > +
> > +#endif /* #else #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
> > +
> > +/* Acquire the specified pthread mutex. */
> > +
> > +static void call_rcu_lock(pthread_mutex_t *pmp)
> > +{
> > + if (pthread_mutex_lock(pmp) != 0) {
> > + perror("pthread_mutex_lock");
> > + exit(-1);
> > + }
> > +}
> > +
> > +/* Release the specified pthread mutex. */
> > +
> > +static void call_rcu_unlock(pthread_mutex_t *pmp)
> > +{
> > + if (pthread_mutex_unlock(pmp) != 0) {
> > + perror("pthread_mutex_unlock");
> > + exit(-1);
> > + }
> > +}
> > +
> > +/* This is the code run by each call_rcu thread. */
> > +
> > +static void *call_rcu_thread(void *arg)
> > +{
> > + unsigned long cbcount;
> > + struct cds_wfq_node *cbs;
> > + struct cds_wfq_node **cbs_tail;
> > + struct call_rcu_data *crdp = (struct call_rcu_data *)arg;
> > + struct rcu_head *rhp;
> > +
> > + thread_call_rcu_data = crdp;
> > + for (;;) {
> > + if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
> > + while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
> > + poll(NULL, 0, 1);
> > + _CMM_STORE_SHARED(crdp->cbs.head, NULL);
> > + cbs_tail = (struct cds_wfq_node **)
> > + uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
> > + synchronize_rcu();
> > + cbcount = 0;
> > + do {
> > + while (cbs->next == NULL &&
> > + &cbs->next != cbs_tail)
> > + poll(NULL, 0, 1);
> > + if (cbs == &crdp->cbs.dummy) {
> > + cbs = cbs->next;
> > + continue;
> > + }
> > + rhp = (struct rcu_head *)cbs;
> > + cbs = cbs->next;
> > + rhp->func(rhp);
> > + cbcount++;
> > + } while (cbs != NULL);
> > + uatomic_sub(&crdp->qlen, cbcount);
> > + }
> > + if (crdp->flags & URCU_CALL_RCU_STOP)
> > + break;
> > + if (crdp->flags & URCU_CALL_RCU_RT)
> > + poll(NULL, 0, 10);
> > + else {
> > + call_rcu_lock(&crdp->mtx);
> > + _CMM_STORE_SHARED(crdp->flags,
> > + crdp->flags & ~URCU_CALL_RCU_RUNNING);
> > + if (&crdp->cbs.head ==
> > + _CMM_LOAD_SHARED(crdp->cbs.tail) &&
> > + pthread_cond_wait(&crdp->cond, &crdp->mtx) != 0) {
> > + perror("pthread_cond_wait");
> > + exit(-1);
> > + }
> > + _CMM_STORE_SHARED(crdp->flags,
> > + crdp->flags | URCU_CALL_RCU_RUNNING);
> > + poll(NULL, 0, 10);
> > + call_rcu_unlock(&crdp->mtx);
> > + }
> > + }
> > + call_rcu_lock(&crdp->mtx);
> > + crdp->flags |= URCU_CALL_RCU_STOPPED;
> > + call_rcu_unlock(&crdp->mtx);
> > + return NULL;
> > +}
> > +
> > +/*
> > + * Create both a call_rcu thread and the corresponding call_rcu_data
> > + * structure, linking the structure in as specified. Caller must hold
> > + * call_rcu_mutex.
> > + */
> > +
> > +static void call_rcu_data_init(struct call_rcu_data **crdpp,
> > + unsigned long flags)
> > +{
> > + struct call_rcu_data *crdp;
> > +
> > + crdp = malloc(sizeof(*crdp));
> > + if (crdp == NULL) {
> > + fprintf(stderr, "Out of memory.\n");
> > + exit(-1);
> > + }
> > + memset(crdp, '\0', sizeof(*crdp));
> > + cds_wfq_init(&crdp->cbs);
> > + crdp->qlen = 0;
> > + if (pthread_mutex_init(&crdp->mtx, NULL) != 0) {
> > + perror("pthread_mutex_init");
> > + exit(-1);
> > + }
> > + if (pthread_cond_init(&crdp->cond, NULL) != 0) {
> > + perror("pthread_cond_init");
> > + exit(-1);
> > + }
> > + crdp->flags = flags | URCU_CALL_RCU_RUNNING;
> > + cds_list_add(&crdp->list, &call_rcu_data_list);
> > + cmm_smp_mb(); /* Structure initialized before pointer is planted. */
> > + *crdpp = crdp;
> > + if (pthread_create(&crdp->tid, NULL, call_rcu_thread, crdp) != 0) {
> > + perror("pthread_create");
> > + exit(-1);
> > + }
> > +}
> > +
> > +/*
> > + * Return a pointer to the call_rcu_data structure for the specified
> > + * CPU, returning NULL if there is none. We cannot automatically
> > + * created it because the platform we are running on might not define
> > + * sched_getcpu().
> > + */
> > +
> > +struct call_rcu_data *get_cpu_call_rcu_data(int cpu)
> > +{
> > + static int warned = 0;
> > +
> > + if (per_cpu_call_rcu_data == NULL)
> > + return NULL;
> > + if (!warned && maxcpus > 0 && (cpu < 0 || maxcpus <= cpu)) {
> > + fprintf(stderr, "[error] liburcu: get CPU # out of range\n");
> > + warned = 1;
> > + }
> > + if (cpu < 0 || maxcpus <= cpu)
> > + return NULL;
> > + return per_cpu_call_rcu_data[cpu];
> > +}
> > +
> > +/*
> > + * Return the tid corresponding to the call_rcu thread whose
> > + * call_rcu_data structure is specified.
> > + */
> > +
> > +pthread_t get_call_rcu_thread(struct call_rcu_data *crdp)
> > +{
> > + return crdp->tid;
> > +}
> > +
> > +/*
> > + * Create a call_rcu_data structure (with thread) and return a pointer.
> > + */
> > +
> > +static struct call_rcu_data *__create_call_rcu_data(unsigned long flags)
> > +{
> > + struct call_rcu_data *crdp;
> > +
> > + call_rcu_data_init(&crdp, flags);
> > + return crdp;
> > +}
> > +
> > +struct call_rcu_data *create_call_rcu_data(unsigned long flags)
> > +{
> > + struct call_rcu_data *crdp;
> > +
> > + call_rcu_lock(&call_rcu_mutex);
> > + crdp = __create_call_rcu_data(flags);
> > + call_rcu_unlock(&call_rcu_mutex);
> > + return crdp;
> > +}
> > +
> > +/*
> > + * Set the specified CPU to use the specified call_rcu_data structure.
> > + *
> > + * Use NULL to remove a CPU's call_rcu_data structure, but it is
> > + * the caller's responsibility to dispose of the removed structure.
> > + * Use get_cpu_call_rcu_data() to obtain a pointer to the old structure
> > + * (prior to NULLing it out, of course).
> > + */
> > +
> > +int set_cpu_call_rcu_data(int cpu, struct call_rcu_data *crdp)
> > +{
> > + int warned = 0;
> > +
> > + call_rcu_lock(&call_rcu_mutex);
> > + if (cpu < 0 || maxcpus <= cpu) {
> > + if (!warned) {
> > + fprintf(stderr, "[error] liburcu: set CPU # out of range\n");
> > + warned = 1;
> > + }
> > + call_rcu_unlock(&call_rcu_mutex);
> > + errno = EINVAL;
> > + return -EINVAL;
> > + }
> > + alloc_cpu_call_rcu_data();
> > + call_rcu_unlock(&call_rcu_mutex);
> > + if (per_cpu_call_rcu_data == NULL) {
> > + errno = ENOMEM;
> > + return -ENOMEM;
> > + }
> > + per_cpu_call_rcu_data[cpu] = crdp;
> > + return 0;
> > +}
> > +
> > +/*
> > + * Return a pointer to the default call_rcu_data structure, creating
> > + * one if need be. Because we never free call_rcu_data structures,
> > + * we don't need to be in an RCU read-side critical section.
> > + */
> > +
> > +struct call_rcu_data *get_default_call_rcu_data(void)
> > +{
> > + if (default_call_rcu_data != NULL)
> > + return rcu_dereference(default_call_rcu_data);
> > + call_rcu_lock(&call_rcu_mutex);
> > + if (default_call_rcu_data != NULL) {
> > + call_rcu_unlock(&call_rcu_mutex);
> > + return default_call_rcu_data;
> > + }
> > + call_rcu_data_init(&default_call_rcu_data, 0);
> > + call_rcu_unlock(&call_rcu_mutex);
> > + return default_call_rcu_data;
> > +}
> > +
> > +/*
> > + * Return the call_rcu_data structure that applies to the currently
> > + * running thread. Any call_rcu_data structure assigned specifically
> > + * to this thread has first priority, followed by any call_rcu_data
> > + * structure assigned to the CPU on which the thread is running,
> > + * followed by the default call_rcu_data structure. If there is not
> > + * yet a default call_rcu_data structure, one will be created.
> > + */
> > +struct call_rcu_data *get_call_rcu_data(void)
> > +{
> > + int curcpu;
> > + static int warned = 0;
> > +
> > + if (thread_call_rcu_data != NULL)
> > + return thread_call_rcu_data;
> > + if (maxcpus <= 0)
> > + return get_default_call_rcu_data();
> > + curcpu = sched_getcpu();
> > + if (!warned && (curcpu < 0 || maxcpus <= curcpu)) {
> > + fprintf(stderr, "[error] liburcu: gcrd CPU # out of range\n");
> > + warned = 1;
> > + }
> > + if (curcpu >= 0 && maxcpus > curcpu &&
> > + per_cpu_call_rcu_data != NULL &&
> > + per_cpu_call_rcu_data[curcpu] != NULL)
> > + return per_cpu_call_rcu_data[curcpu];
> > + return get_default_call_rcu_data();
> > +}
> > +
> > +/*
> > + * Return a pointer to this task's call_rcu_data if there is one.
> > + */
> > +
> > +struct call_rcu_data *get_thread_call_rcu_data(void)
> > +{
> > + return thread_call_rcu_data;
> > +}
> > +
> > +/*
> > + * Set this task's call_rcu_data structure as specified, regardless
> > + * of whether or not this task already had one. (This allows switching
> > + * to and from real-time call_rcu threads, for example.)
> > + *
> > + * Use NULL to remove a thread's call_rcu_data structure, but it is
> > + * the caller's responsibility to dispose of the removed structure.
> > + * Use get_thread_call_rcu_data() to obtain a pointer to the old structure
> > + * (prior to NULLing it out, of course).
> > + */
> > +
> > +void set_thread_call_rcu_data(struct call_rcu_data *crdp)
> > +{
> > + thread_call_rcu_data = crdp;
> > +}
> > +
> > +/*
> > + * Create a separate call_rcu thread for each CPU. This does not
> > + * replace a pre-existing call_rcu thread -- use the set_cpu_call_rcu_data()
> > + * function if you want that behavior.
> > + */
> > +
> > +int create_all_cpu_call_rcu_data(unsigned long flags)
> > +{
> > + int i;
> > + struct call_rcu_data *crdp;
> > + int ret;
> > +
> > + call_rcu_lock(&call_rcu_mutex);
> > + alloc_cpu_call_rcu_data();
> > + call_rcu_unlock(&call_rcu_mutex);
> > + if (maxcpus <= 0) {
> > + errno = EINVAL;
> > + return -EINVAL;
> > + }
> > + if (per_cpu_call_rcu_data == NULL) {
> > + errno = ENOMEM;
> > + return -ENOMEM;
> > + }
> > + for (i = 0; i < maxcpus; i++) {
> > + call_rcu_lock(&call_rcu_mutex);
> > + if (get_cpu_call_rcu_data(i)) {
> > + call_rcu_unlock(&call_rcu_mutex);
> > + continue;
> > + }
> > + crdp = __create_call_rcu_data(flags);
> > + if (crdp == NULL) {
> > + call_rcu_unlock(&call_rcu_mutex);
> > + errno = ENOMEM;
> > + return -ENOMEM;
> > + }
> > + call_rcu_unlock(&call_rcu_mutex);
> > + if ((ret = set_cpu_call_rcu_data(i, crdp)) != 0) {
> > + /* FIXME: Leaks crdp for now. */
> > + return ret; /* Can happen on race. */
> > + }
> > + }
> > + return 0;
> > +}
> > +
> > +/*
> > + * Wake up the call_rcu thread corresponding to the specified
> > + * call_rcu_data structure.
> > + */
> > +static void wake_call_rcu_thread(struct call_rcu_data *crdp)
> > +{
> > + if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RT)) {
> > + call_rcu_lock(&crdp->mtx);
> > + if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RUNNING)) {
> > + if (pthread_cond_signal(&crdp->cond) != 0) {
> > + perror("pthread_cond_signal");
> > + exit(-1);
> > + }
> > + }
> > + call_rcu_unlock(&crdp->mtx);
> > + }
> > +}
> > +
> > +/*
> > + * Schedule a function to be invoked after a following grace period.
> > + * This is the only function that must be called -- the others are
> > + * only present to allow applications to tune their use of RCU for
> > + * maximum performance.
> > + *
> > + * Note that unless a call_rcu thread has not already been created,
> > + * the first invocation of call_rcu() will create one. So, if you
> > + * need the first invocation of call_rcu() to be fast, make sure
> > + * to create a call_rcu thread first. One way to accomplish this is
> > + * "get_call_rcu_data();", and another is create_all_cpu_call_rcu_data().
> > + */
> > +
> > +void call_rcu(struct rcu_head *head,
> > + void (*func)(struct rcu_head *head))
> > +{
> > + struct call_rcu_data *crdp;
> > +
> > + cds_wfq_node_init(&head->next);
> > + head->func = func;
> > + crdp = get_call_rcu_data();
> > + cds_wfq_enqueue(&crdp->cbs, &head->next);
> > + uatomic_inc(&crdp->qlen);
> > + wake_call_rcu_thread(crdp);
> > +}
> > +
> > +/*
> > + * Free up the specified call_rcu_data structure, terminating the
> > + * associated call_rcu thread. The caller must have previously
> > + * removed the call_rcu_data structure from per-thread or per-CPU
> > + * usage. For example, set_cpu_call_rcu_data(cpu, NULL) for per-CPU
> > + * call_rcu_data structures or set_thread_call_rcu_data(NULL) for
> > + * per-thread call_rcu_data structures.
> > + *
> > + * We silently refuse to free up the default call_rcu_data structure
> > + * because that is where we put any leftover callbacks. Note that
> > + * the possibility of self-spawning callbacks makes it impossible
> > + * to execute all the callbacks in finite time without putting any
> > + * newly spawned callbacks somewhere else. The "somewhere else" of
> > + * last resort is the default call_rcu_data structure.
> > + *
> > + * We also silently refuse to free NULL pointers. This simplifies
> > + * the calling code.
> > + */
> > +void call_rcu_data_free(struct call_rcu_data *crdp)
> > +{
> > + struct cds_wfq_node *cbs;
> > + struct cds_wfq_node **cbs_tail;
> > + struct cds_wfq_node **cbs_endprev;
> > +
> > + if (crdp == NULL || crdp == default_call_rcu_data) {
> > + return;
> > + }
> > + if ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0) {
> > + call_rcu_lock(&crdp->mtx);
> > + crdp->flags |= URCU_CALL_RCU_STOP;
> > + call_rcu_unlock(&crdp->mtx);
> > + wake_call_rcu_thread(crdp);
> > + while ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0)
> > + poll(NULL, 0, 1);
> > + }
> > + if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
> > + while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
> > + poll(NULL, 0, 1);
> > + _CMM_STORE_SHARED(crdp->cbs.head, NULL);
> > + cbs_tail = (struct cds_wfq_node **)
> > + uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
> > + cbs_endprev = (struct cds_wfq_node **)
> > + uatomic_xchg(&default_call_rcu_data, cbs_tail);
> > + *cbs_endprev = cbs;
> > + uatomic_add(&default_call_rcu_data->qlen,
> > + uatomic_read(&crdp->qlen));
> > + cds_list_del(&crdp->list);
> > + free(crdp);
> > + }
> > +}
> > +
> > +/*
> > + * Clean up all the per-CPU call_rcu threads.
> > + */
> > +void free_all_cpu_call_rcu_data(void)
> > +{
> > + int cpu;
> > + struct call_rcu_data *crdp;
> > +
> > + if (maxcpus <= 0)
> > + return;
> > + for (cpu = 0; cpu < maxcpus; cpu++) {
> > + crdp = get_cpu_call_rcu_data(cpu);
> > + if (crdp == NULL)
> > + continue;
> > + set_cpu_call_rcu_data(cpu, NULL);
> > + call_rcu_data_free(crdp);
> > + }
> > +}
> > +
> > +/*
> > + * Acquire the call_rcu_mutex in order to ensure that the child sees
> > + * all of the call_rcu() data structures in a consistent state.
> > + * Suitable for pthread_atfork() and friends.
> > + */
> > +void call_rcu_before_fork(void)
> > +{
> > + call_rcu_lock(&call_rcu_mutex);
> > +}
> > +
> > +/*
> > + * Clean up call_rcu data structures in the parent of a successful fork()
> > + * that is not followed by exec() in the child. Suitable for
> > + * pthread_atfork() and friends.
> > + */
> > +void call_rcu_after_fork_parent(void)
> > +{
> > + call_rcu_unlock(&call_rcu_mutex);
> > +}
> > +
> > +/*
> > + * Clean up call_rcu data structures in the child of a successful fork()
> > + * that is not followed by exec(). Suitable for pthread_atfork() and
> > + * friends.
> > + */
> > +void call_rcu_after_fork_child(void)
> > +{
> > + struct call_rcu_data *crdp;
> > +
> > + /* Re-initialize the mutex. */
> > + if (pthread_mutex_init(&call_rcu_mutex, NULL) != 0) {
> > + perror("pthread_mutex_init");
> > + exit(-1);
> > + }
> > +
> > + /*
> > + * Allocate a new default call_rcu_data structure in order
> > + * to get a working call_rcu thread to go with it.
> > + */
> > + default_call_rcu_data = NULL;
> > + (void)get_default_call_rcu_data();
> > +
> > + /* Dispose of all of the rest of the call_rcu_data structures. */
> > + while (call_rcu_data_list.next != call_rcu_data_list.prev) {
> > + crdp = cds_list_entry(call_rcu_data_list.prev,
> > + struct call_rcu_data, list);
> > + if (crdp == default_call_rcu_data)
> > + crdp = cds_list_entry(crdp->list.prev,
> > + struct call_rcu_data, list);
> > + crdp->flags = URCU_CALL_RCU_STOPPED;
> > + call_rcu_data_free(crdp);
> > + }
> > +}
> > diff --git a/urcu-call-rcu.c b/urcu-call-rcu.c
> > deleted file mode 100644
> > index 665f20c..0000000
> > --- a/urcu-call-rcu.c
> > +++ /dev/null
> > @@ -1,620 +0,0 @@
> > -/*
> > - * urcu-call-rcu.c
> > - *
> > - * Userspace RCU library - batch memory reclamation with kernel API
> > - *
> > - * Copyright (c) 2010 Paul E. McKenney <paulmck at linux.vnet.ibm.com>
> > - *
> > - * This library is free software; you can redistribute it and/or
> > - * modify it under the terms of the GNU Lesser General Public
> > - * License as published by the Free Software Foundation; either
> > - * version 2.1 of the License, or (at your option) any later version.
> > - *
> > - * This library is distributed in the hope that it will be useful,
> > - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > - * Lesser General Public License for more details.
> > - *
> > - * You should have received a copy of the GNU Lesser General Public
> > - * License along with this library; if not, write to the Free Software
> > - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> > - */
> > -
> > -#include <stdio.h>
> > -#include <pthread.h>
> > -#include <signal.h>
> > -#include <assert.h>
> > -#include <stdlib.h>
> > -#include <string.h>
> > -#include <errno.h>
> > -#include <poll.h>
> > -#include <sys/time.h>
> > -#include <syscall.h>
> > -#include <unistd.h>
> > -
> > -#include "config.h"
> > -#include "urcu/wfqueue.h"
> > -#include "urcu-call-rcu.h"
> > -#include "urcu-pointer.h"
> > -#include "urcu/list.h"
> > -
> > -/* Data structure that identifies a call_rcu thread. */
> > -
> > -struct call_rcu_data {
> > - struct cds_wfq_queue cbs;
> > - unsigned long flags;
> > - pthread_mutex_t mtx;
> > - pthread_cond_t cond;
> > - unsigned long qlen;
> > - pthread_t tid;
> > - struct cds_list_head list;
> > -} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
> > -
> > -/*
> > - * List of all call_rcu_data structures to keep valgrind happy.
> > - * Protected by call_rcu_mutex.
> > - */
> > -
> > -CDS_LIST_HEAD(call_rcu_data_list);
> > -
> > -/* Link a thread using call_rcu() to its call_rcu thread. */
> > -
> > -static __thread struct call_rcu_data *thread_call_rcu_data;
> > -
> > -/* Guard call_rcu thread creation. */
> > -
> > -static pthread_mutex_t call_rcu_mutex = PTHREAD_MUTEX_INITIALIZER;
> > -
> > -/* If a given thread does not have its own call_rcu thread, this is default. */
> > -
> > -static struct call_rcu_data *default_call_rcu_data;
> > -
> > -extern void synchronize_rcu(void);
> > -
> > -/*
> > - * If the sched_getcpu() and sysconf(_SC_NPROCESSORS_CONF) calls are
> > - * available, then we can have call_rcu threads assigned to individual
> > - * CPUs rather than only to specific threads.
> > - */
> > -
> > -#if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF)
> > -
> > -/*
> > - * Pointer to array of pointers to per-CPU call_rcu_data structures
> > - * and # CPUs.
> > - */
> > -
> > -static struct call_rcu_data **per_cpu_call_rcu_data;
> > -static long maxcpus;
> > -
> > -/* Allocate the array if it has not already been allocated. */
> > -
> > -static void alloc_cpu_call_rcu_data(void)
> > -{
> > - struct call_rcu_data **p;
> > - static int warned = 0;
> > -
> > - if (maxcpus != 0)
> > - return;
> > - maxcpus = sysconf(_SC_NPROCESSORS_CONF);
> > - if (maxcpus <= 0) {
> > - return;
> > - }
> > - p = malloc(maxcpus * sizeof(*per_cpu_call_rcu_data));
> > - if (p != NULL) {
> > - memset(p, '\0', maxcpus * sizeof(*per_cpu_call_rcu_data));
> > - per_cpu_call_rcu_data = p;
> > - } else {
> > - if (!warned) {
> > - fprintf(stderr, "[error] liburcu: unable to allocate per-CPU pointer array\n");
> > - }
> > - warned = 1;
> > - }
> > -}
> > -
> > -#else /* #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
> > -
> > -static const struct call_rcu_data **per_cpu_call_rcu_data = NULL;
> > -static const long maxcpus = -1;
> > -
> > -static void alloc_cpu_call_rcu_data(void)
> > -{
> > -}
> > -
> > -static int sched_getcpu(void)
> > -{
> > - return -1;
> > -}
> > -
> > -#endif /* #else #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */
> > -
> > -/* Acquire the specified pthread mutex. */
> > -
> > -static void call_rcu_lock(pthread_mutex_t *pmp)
> > -{
> > - if (pthread_mutex_lock(pmp) != 0) {
> > - perror("pthread_mutex_lock");
> > - exit(-1);
> > - }
> > -}
> > -
> > -/* Release the specified pthread mutex. */
> > -
> > -static void call_rcu_unlock(pthread_mutex_t *pmp)
> > -{
> > - if (pthread_mutex_unlock(pmp) != 0) {
> > - perror("pthread_mutex_unlock");
> > - exit(-1);
> > - }
> > -}
> > -
> > -/* This is the code run by each call_rcu thread. */
> > -
> > -static void *call_rcu_thread(void *arg)
> > -{
> > - unsigned long cbcount;
> > - struct cds_wfq_node *cbs;
> > - struct cds_wfq_node **cbs_tail;
> > - struct call_rcu_data *crdp = (struct call_rcu_data *)arg;
> > - struct rcu_head *rhp;
> > -
> > - thread_call_rcu_data = crdp;
> > - for (;;) {
> > - if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
> > - while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
> > - poll(NULL, 0, 1);
> > - _CMM_STORE_SHARED(crdp->cbs.head, NULL);
> > - cbs_tail = (struct cds_wfq_node **)
> > - uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
> > - synchronize_rcu();
> > - cbcount = 0;
> > - do {
> > - while (cbs->next == NULL &&
> > - &cbs->next != cbs_tail)
> > - poll(NULL, 0, 1);
> > - if (cbs == &crdp->cbs.dummy) {
> > - cbs = cbs->next;
> > - continue;
> > - }
> > - rhp = (struct rcu_head *)cbs;
> > - cbs = cbs->next;
> > - rhp->func(rhp);
> > - cbcount++;
> > - } while (cbs != NULL);
> > - uatomic_sub(&crdp->qlen, cbcount);
> > - }
> > - if (crdp->flags & URCU_CALL_RCU_STOP)
> > - break;
> > - if (crdp->flags & URCU_CALL_RCU_RT)
> > - poll(NULL, 0, 10);
> > - else {
> > - call_rcu_lock(&crdp->mtx);
> > - _CMM_STORE_SHARED(crdp->flags,
> > - crdp->flags & ~URCU_CALL_RCU_RUNNING);
> > - if (&crdp->cbs.head ==
> > - _CMM_LOAD_SHARED(crdp->cbs.tail) &&
> > - pthread_cond_wait(&crdp->cond, &crdp->mtx) != 0) {
> > - perror("pthread_cond_wait");
> > - exit(-1);
> > - }
> > - _CMM_STORE_SHARED(crdp->flags,
> > - crdp->flags | URCU_CALL_RCU_RUNNING);
> > - poll(NULL, 0, 10);
> > - call_rcu_unlock(&crdp->mtx);
> > - }
> > - }
> > - call_rcu_lock(&crdp->mtx);
> > - crdp->flags |= URCU_CALL_RCU_STOPPED;
> > - call_rcu_unlock(&crdp->mtx);
> > - return NULL;
> > -}
> > -
> > -/*
> > - * Create both a call_rcu thread and the corresponding call_rcu_data
> > - * structure, linking the structure in as specified. Caller must hold
> > - * call_rcu_mutex.
> > - */
> > -
> > -static void call_rcu_data_init(struct call_rcu_data **crdpp,
> > - unsigned long flags)
> > -{
> > - struct call_rcu_data *crdp;
> > -
> > - crdp = malloc(sizeof(*crdp));
> > - if (crdp == NULL) {
> > - fprintf(stderr, "Out of memory.\n");
> > - exit(-1);
> > - }
> > - memset(crdp, '\0', sizeof(*crdp));
> > - cds_wfq_init(&crdp->cbs);
> > - crdp->qlen = 0;
> > - if (pthread_mutex_init(&crdp->mtx, NULL) != 0) {
> > - perror("pthread_mutex_init");
> > - exit(-1);
> > - }
> > - if (pthread_cond_init(&crdp->cond, NULL) != 0) {
> > - perror("pthread_cond_init");
> > - exit(-1);
> > - }
> > - crdp->flags = flags | URCU_CALL_RCU_RUNNING;
> > - cds_list_add(&crdp->list, &call_rcu_data_list);
> > - cmm_smp_mb(); /* Structure initialized before pointer is planted. */
> > - *crdpp = crdp;
> > - if (pthread_create(&crdp->tid, NULL, call_rcu_thread, crdp) != 0) {
> > - perror("pthread_create");
> > - exit(-1);
> > - }
> > -}
> > -
> > -/*
> > - * Return a pointer to the call_rcu_data structure for the specified
> > - * CPU, returning NULL if there is none. We cannot automatically
> > - * created it because the platform we are running on might not define
> > - * sched_getcpu().
> > - */
> > -
> > -struct call_rcu_data *get_cpu_call_rcu_data(int cpu)
> > -{
> > - static int warned = 0;
> > -
> > - if (per_cpu_call_rcu_data == NULL)
> > - return NULL;
> > - if (!warned && maxcpus > 0 && (cpu < 0 || maxcpus <= cpu)) {
> > - fprintf(stderr, "[error] liburcu: get CPU # out of range\n");
> > - warned = 1;
> > - }
> > - if (cpu < 0 || maxcpus <= cpu)
> > - return NULL;
> > - return per_cpu_call_rcu_data[cpu];
> > -}
> > -
> > -/*
> > - * Return the tid corresponding to the call_rcu thread whose
> > - * call_rcu_data structure is specified.
> > - */
> > -
> > -pthread_t get_call_rcu_thread(struct call_rcu_data *crdp)
> > -{
> > - return crdp->tid;
> > -}
> > -
> > -/*
> > - * Create a call_rcu_data structure (with thread) and return a pointer.
> > - */
> > -
> > -static struct call_rcu_data *__create_call_rcu_data(unsigned long flags)
> > -{
> > - struct call_rcu_data *crdp;
> > -
> > - call_rcu_data_init(&crdp, flags);
> > - return crdp;
> > -}
> > -
> > -struct call_rcu_data *create_call_rcu_data(unsigned long flags)
> > -{
> > - struct call_rcu_data *crdp;
> > -
> > - call_rcu_lock(&call_rcu_mutex);
> > - crdp = __create_call_rcu_data(flags);
> > - call_rcu_unlock(&call_rcu_mutex);
> > - return crdp;
> > -}
> > -
> > -/*
> > - * Set the specified CPU to use the specified call_rcu_data structure.
> > - *
> > - * Use NULL to remove a CPU's call_rcu_data structure, but it is
> > - * the caller's responsibility to dispose of the removed structure.
> > - * Use get_cpu_call_rcu_data() to obtain a pointer to the old structure
> > - * (prior to NULLing it out, of course).
> > - */
> > -
> > -int set_cpu_call_rcu_data(int cpu, struct call_rcu_data *crdp)
> > -{
> > - int warned = 0;
> > -
> > - call_rcu_lock(&call_rcu_mutex);
> > - if (cpu < 0 || maxcpus <= cpu) {
> > - if (!warned) {
> > - fprintf(stderr, "[error] liburcu: set CPU # out of range\n");
> > - warned = 1;
> > - }
> > - call_rcu_unlock(&call_rcu_mutex);
> > - errno = EINVAL;
> > - return -EINVAL;
> > - }
> > - alloc_cpu_call_rcu_data();
> > - call_rcu_unlock(&call_rcu_mutex);
> > - if (per_cpu_call_rcu_data == NULL) {
> > - errno = ENOMEM;
> > - return -ENOMEM;
> > - }
> > - per_cpu_call_rcu_data[cpu] = crdp;
> > - return 0;
> > -}
> > -
> > -/*
> > - * Return a pointer to the default call_rcu_data structure, creating
> > - * one if need be. Because we never free call_rcu_data structures,
> > - * we don't need to be in an RCU read-side critical section.
> > - */
> > -
> > -struct call_rcu_data *get_default_call_rcu_data(void)
> > -{
> > - if (default_call_rcu_data != NULL)
> > - return rcu_dereference(default_call_rcu_data);
> > - call_rcu_lock(&call_rcu_mutex);
> > - if (default_call_rcu_data != NULL) {
> > - call_rcu_unlock(&call_rcu_mutex);
> > - return default_call_rcu_data;
> > - }
> > - call_rcu_data_init(&default_call_rcu_data, 0);
> > - call_rcu_unlock(&call_rcu_mutex);
> > - return default_call_rcu_data;
> > -}
> > -
> > -/*
> > - * Return the call_rcu_data structure that applies to the currently
> > - * running thread. Any call_rcu_data structure assigned specifically
> > - * to this thread has first priority, followed by any call_rcu_data
> > - * structure assigned to the CPU on which the thread is running,
> > - * followed by the default call_rcu_data structure. If there is not
> > - * yet a default call_rcu_data structure, one will be created.
> > - */
> > -struct call_rcu_data *get_call_rcu_data(void)
> > -{
> > - int curcpu;
> > - static int warned = 0;
> > -
> > - if (thread_call_rcu_data != NULL)
> > - return thread_call_rcu_data;
> > - if (maxcpus <= 0)
> > - return get_default_call_rcu_data();
> > - curcpu = sched_getcpu();
> > - if (!warned && (curcpu < 0 || maxcpus <= curcpu)) {
> > - fprintf(stderr, "[error] liburcu: gcrd CPU # out of range\n");
> > - warned = 1;
> > - }
> > - if (curcpu >= 0 && maxcpus > curcpu &&
> > - per_cpu_call_rcu_data != NULL &&
> > - per_cpu_call_rcu_data[curcpu] != NULL)
> > - return per_cpu_call_rcu_data[curcpu];
> > - return get_default_call_rcu_data();
> > -}
> > -
> > -/*
> > - * Return a pointer to this task's call_rcu_data if there is one.
> > - */
> > -
> > -struct call_rcu_data *get_thread_call_rcu_data(void)
> > -{
> > - return thread_call_rcu_data;
> > -}
> > -
> > -/*
> > - * Set this task's call_rcu_data structure as specified, regardless
> > - * of whether or not this task already had one. (This allows switching
> > - * to and from real-time call_rcu threads, for example.)
> > - *
> > - * Use NULL to remove a thread's call_rcu_data structure, but it is
> > - * the caller's responsibility to dispose of the removed structure.
> > - * Use get_thread_call_rcu_data() to obtain a pointer to the old structure
> > - * (prior to NULLing it out, of course).
> > - */
> > -
> > -void set_thread_call_rcu_data(struct call_rcu_data *crdp)
> > -{
> > - thread_call_rcu_data = crdp;
> > -}
> > -
> > -/*
> > - * Create a separate call_rcu thread for each CPU. This does not
> > - * replace a pre-existing call_rcu thread -- use the set_cpu_call_rcu_data()
> > - * function if you want that behavior.
> > - */
> > -
> > -int create_all_cpu_call_rcu_data(unsigned long flags)
> > -{
> > - int i;
> > - struct call_rcu_data *crdp;
> > - int ret;
> > -
> > - call_rcu_lock(&call_rcu_mutex);
> > - alloc_cpu_call_rcu_data();
> > - call_rcu_unlock(&call_rcu_mutex);
> > - if (maxcpus <= 0) {
> > - errno = EINVAL;
> > - return -EINVAL;
> > - }
> > - if (per_cpu_call_rcu_data == NULL) {
> > - errno = ENOMEM;
> > - return -ENOMEM;
> > - }
> > - for (i = 0; i < maxcpus; i++) {
> > - call_rcu_lock(&call_rcu_mutex);
> > - if (get_cpu_call_rcu_data(i)) {
> > - call_rcu_unlock(&call_rcu_mutex);
> > - continue;
> > - }
> > - crdp = __create_call_rcu_data(flags);
> > - if (crdp == NULL) {
> > - call_rcu_unlock(&call_rcu_mutex);
> > - errno = ENOMEM;
> > - return -ENOMEM;
> > - }
> > - call_rcu_unlock(&call_rcu_mutex);
> > - if ((ret = set_cpu_call_rcu_data(i, crdp)) != 0) {
> > - /* FIXME: Leaks crdp for now. */
> > - return ret; /* Can happen on race. */
> > - }
> > - }
> > - return 0;
> > -}
> > -
> > -/*
> > - * Wake up the call_rcu thread corresponding to the specified
> > - * call_rcu_data structure.
> > - */
> > -static void wake_call_rcu_thread(struct call_rcu_data *crdp)
> > -{
> > - if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RT)) {
> > - call_rcu_lock(&crdp->mtx);
> > - if (!(_CMM_LOAD_SHARED(crdp->flags) & URCU_CALL_RCU_RUNNING)) {
> > - if (pthread_cond_signal(&crdp->cond) != 0) {
> > - perror("pthread_cond_signal");
> > - exit(-1);
> > - }
> > - }
> > - call_rcu_unlock(&crdp->mtx);
> > - }
> > -}
> > -
> > -/*
> > - * Schedule a function to be invoked after a following grace period.
> > - * This is the only function that must be called -- the others are
> > - * only present to allow applications to tune their use of RCU for
> > - * maximum performance.
> > - *
> > - * Note that unless a call_rcu thread has not already been created,
> > - * the first invocation of call_rcu() will create one. So, if you
> > - * need the first invocation of call_rcu() to be fast, make sure
> > - * to create a call_rcu thread first. One way to accomplish this is
> > - * "get_call_rcu_data();", and another is create_all_cpu_call_rcu_data().
> > - */
> > -
> > -void call_rcu(struct rcu_head *head,
> > - void (*func)(struct rcu_head *head))
> > -{
> > - struct call_rcu_data *crdp;
> > -
> > - cds_wfq_node_init(&head->next);
> > - head->func = func;
> > - crdp = get_call_rcu_data();
> > - cds_wfq_enqueue(&crdp->cbs, &head->next);
> > - uatomic_inc(&crdp->qlen);
> > - wake_call_rcu_thread(crdp);
> > -}
> > -
> > -/*
> > - * Free up the specified call_rcu_data structure, terminating the
> > - * associated call_rcu thread. The caller must have previously
> > - * removed the call_rcu_data structure from per-thread or per-CPU
> > - * usage. For example, set_cpu_call_rcu_data(cpu, NULL) for per-CPU
> > - * call_rcu_data structures or set_thread_call_rcu_data(NULL) for
> > - * per-thread call_rcu_data structures.
> > - *
> > - * We silently refuse to free up the default call_rcu_data structure
> > - * because that is where we put any leftover callbacks. Note that
> > - * the possibility of self-spawning callbacks makes it impossible
> > - * to execute all the callbacks in finite time without putting any
> > - * newly spawned callbacks somewhere else. The "somewhere else" of
> > - * last resort is the default call_rcu_data structure.
> > - *
> > - * We also silently refuse to free NULL pointers. This simplifies
> > - * the calling code.
> > - */
> > -void call_rcu_data_free(struct call_rcu_data *crdp)
> > -{
> > - struct cds_wfq_node *cbs;
> > - struct cds_wfq_node **cbs_tail;
> > - struct cds_wfq_node **cbs_endprev;
> > -
> > - if (crdp == NULL || crdp == default_call_rcu_data) {
> > - return;
> > - }
> > - if ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0) {
> > - call_rcu_lock(&crdp->mtx);
> > - crdp->flags |= URCU_CALL_RCU_STOP;
> > - call_rcu_unlock(&crdp->mtx);
> > - wake_call_rcu_thread(crdp);
> > - while ((crdp->flags & URCU_CALL_RCU_STOPPED) == 0)
> > - poll(NULL, 0, 1);
> > - }
> > - if (&crdp->cbs.head != _CMM_LOAD_SHARED(crdp->cbs.tail)) {
> > - while ((cbs = _CMM_LOAD_SHARED(crdp->cbs.head)) == NULL)
> > - poll(NULL, 0, 1);
> > - _CMM_STORE_SHARED(crdp->cbs.head, NULL);
> > - cbs_tail = (struct cds_wfq_node **)
> > - uatomic_xchg(&crdp->cbs.tail, &crdp->cbs.head);
> > - cbs_endprev = (struct cds_wfq_node **)
> > - uatomic_xchg(&default_call_rcu_data, cbs_tail);
> > - *cbs_endprev = cbs;
> > - uatomic_add(&default_call_rcu_data->qlen,
> > - uatomic_read(&crdp->qlen));
> > - cds_list_del(&crdp->list);
> > - free(crdp);
> > - }
> > -}
> > -
> > -/*
> > - * Clean up all the per-CPU call_rcu threads.
> > - */
> > -void free_all_cpu_call_rcu_data(void)
> > -{
> > - int cpu;
> > - struct call_rcu_data *crdp;
> > -
> > - if (maxcpus <= 0)
> > - return;
> > - for (cpu = 0; cpu < maxcpus; cpu++) {
> > - crdp = get_cpu_call_rcu_data(cpu);
> > - if (crdp == NULL)
> > - continue;
> > - set_cpu_call_rcu_data(cpu, NULL);
> > - call_rcu_data_free(crdp);
> > - }
> > -}
> > -
> > -/*
> > - * Acquire the call_rcu_mutex in order to ensure that the child sees
> > - * all of the call_rcu() data structures in a consistent state.
> > - * Suitable for pthread_atfork() and friends.
> > - */
> > -void call_rcu_before_fork(void)
> > -{
> > - call_rcu_lock(&call_rcu_mutex);
> > -}
> > -
> > -/*
> > - * Clean up call_rcu data structures in the parent of a successful fork()
> > - * that is not followed by exec() in the child. Suitable for
> > - * pthread_atfork() and friends.
> > - */
> > -void call_rcu_after_fork_parent(void)
> > -{
> > - call_rcu_unlock(&call_rcu_mutex);
> > -}
> > -
> > -/*
> > - * Clean up call_rcu data structures in the child of a successful fork()
> > - * that is not followed by exec(). Suitable for pthread_atfork() and
> > - * friends.
> > - */
> > -void call_rcu_after_fork_child(void)
> > -{
> > - struct call_rcu_data *crdp;
> > -
> > - /* Re-initialize the mutex. */
> > - if (pthread_mutex_init(&call_rcu_mutex, NULL) != 0) {
> > - perror("pthread_mutex_init");
> > - exit(-1);
> > - }
> > -
> > - /*
> > - * Allocate a new default call_rcu_data structure in order
> > - * to get a working call_rcu thread to go with it.
> > - */
> > - default_call_rcu_data = NULL;
> > - (void)get_default_call_rcu_data();
> > -
> > - /* Dispose of all of the rest of the call_rcu_data structures. */
> > - while (call_rcu_data_list.next != call_rcu_data_list.prev) {
> > - crdp = cds_list_entry(call_rcu_data_list.prev,
> > - struct call_rcu_data, list);
> > - if (crdp == default_call_rcu_data)
> > - crdp = cds_list_entry(crdp->list.prev,
> > - struct call_rcu_data, list);
> > - crdp->flags = URCU_CALL_RCU_STOPPED;
> > - call_rcu_data_free(crdp);
> > - }
> > -}
> > diff --git a/urcu-map.h b/urcu-map.h
> > new file mode 100644
> > index 0000000..eccaac2
> > --- /dev/null
> > +++ b/urcu-map.h
> > @@ -0,0 +1,117 @@
> > +#ifndef _URCU_MAP_H
> > +#define _URCU_MAP_H
> > +
> > +/*
> > + * urcu-map.h
> > + *
> > + * Userspace RCU header -- name mapping to allow multiple flavors to be
> > + * used in the same executable.
> > + *
> > + * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> > + * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
> > + *
> > + * LGPL-compatible code should include this header with :
> > + *
> > + * #define _LGPL_SOURCE
> > + * #include <urcu.h>
> > + *
> > + * This library is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU Lesser General Public
> > + * License as published by the Free Software Foundation; either
> > + * version 2.1 of the License, or (at your option) any later version.
> > + *
> > + * This library is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * Lesser General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU Lesser General Public
> > + * License along with this library; if not, write to the Free Software
> > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> > + *
> > + * IBM's contributions to this file may be relicensed under LGPLv2 or later.
> > + */
> > +
> > +/* Mapping macros to allow multiple flavors in a single binary. */
> > +
> > +#ifdef RCU_MEMBARRIER
> > +
> > +#define rcu_read_lock rcu_read_lock_memb
> > +#define _rcu_read_lock _rcu_read_lock_memb
> > +#define rcu_read_unlock rcu_read_unlock_memb
> > +#define _rcu_read_unlock _rcu_read_unlock_memb
> > +#define rcu_register_thread rcu_register_thread_memb
> > +#define rcu_unregister_thread rcu_unregister_thread_memb
> > +#define rcu_init rcu_init_memb
> > +#define rcu_exit rcu_exit_memb
> > +#define synchronize_rcu synchronize_rcu_memb
> > +#define rcu_reader rcu_reader_memb
> > +#define rcu_gp_ctr rcu_gp_ctr_memb
> > +
> > +#define get_cpu_call_rcu_data get_cpu_call_rcu_data_memb
> > +#define get_call_rcu_thread get_call_rcu_thread_memb
> > +#define create_call_rcu_data create_call_rcu_data_memb
> > +#define set_cpu_call_rcu_data set_cpu_call_rcu_data_memb
> > +#define get_default_call_rcu_data get_default_call_rcu_data_memb
> > +#define get_call_rcu_data get_call_rcu_data_memb
> > +#define get_thread_call_rcu_data get_thread_call_rcu_data_memb
> > +#define set_thread_call_rcu_data set_thread_call_rcu_data_memb
> > +#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_memb
> > +#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_memb
> > +#define call_rcu call_rcu_memb
> > +
> > +#elif defined(RCU_SIGNAL)
> > +
> > +#define rcu_read_lock rcu_read_lock_sig
> > +#define _rcu_read_lock _rcu_read_lock_sig
> > +#define rcu_read_unlock rcu_read_unlock_sig
> > +#define _rcu_read_unlock _rcu_read_unlock_sig
> > +#define rcu_register_thread rcu_register_thread_sig
> > +#define rcu_unregister_thread rcu_unregister_thread_sig
> > +#define rcu_init rcu_init_sig
> > +#define rcu_exit rcu_exit_sig
> > +#define synchronize_rcu synchronize_rcu_sig
> > +#define rcu_reader rcu_reader_sig
> > +#define rcu_gp_ctr rcu_gp_ctr_sig
> > +
> > +#define get_cpu_call_rcu_data get_cpu_call_rcu_data_sig
> > +#define get_call_rcu_thread get_call_rcu_thread_sig
> > +#define create_call_rcu_data create_call_rcu_data_sig
> > +#define set_cpu_call_rcu_data set_cpu_call_rcu_data_sig
> > +#define get_default_call_rcu_data get_default_call_rcu_data_sig
> > +#define get_call_rcu_data get_call_rcu_data_sig
> > +#define get_thread_call_rcu_data get_thread_call_rcu_data_sig
> > +#define set_thread_call_rcu_data set_thread_call_rcu_data_sig
> > +#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_sig
> > +#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_sig
> > +#define call_rcu call_rcu_sig
> > +
> > +#elif defined(RCU_MB)
> > +
> > +#define rcu_read_lock rcu_read_lock_mb
> > +#define _rcu_read_lock _rcu_read_lock_mb
> > +#define rcu_read_unlock rcu_read_unlock_mb
> > +#define _rcu_read_unlock _rcu_read_unlock_mb
> > +#define rcu_register_thread rcu_register_thread_mb
> > +#define rcu_unregister_thread rcu_unregister_thread_mb
> > +#define rcu_init rcu_init_mb
> > +#define rcu_exit rcu_exit_mb
> > +#define synchronize_rcu synchronize_rcu_mb
> > +#define rcu_reader rcu_reader_mb
> > +#define rcu_gp_ctr rcu_gp_ctr_mb
> > +
> > +#define get_cpu_call_rcu_data get_cpu_call_rcu_data_mb
> > +#define get_call_rcu_thread get_call_rcu_thread_mb
> > +#define create_call_rcu_data create_call_rcu_data_mb
> > +#define set_cpu_call_rcu_data set_cpu_call_rcu_data_mb
> > +#define get_default_call_rcu_data get_default_call_rcu_data_mb
> > +#define get_call_rcu_data get_call_rcu_data_mb
> > +#define get_thread_call_rcu_data get_thread_call_rcu_data_mb
> > +#define set_thread_call_rcu_data set_thread_call_rcu_data_mb
> > +#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_mb
> > +#define free_all_cpu_call_rcu_data free_all_cpu_call_rcu_data_mb
> > +#define call_rcu call_rcu_mb
> > +
> > +#endif
> > +
> > +#endif /* _URCU_MAP_H */
> > diff --git a/urcu-qsbr-map.h b/urcu-qsbr-map.h
> > new file mode 100644
> > index 0000000..2bce1b6
> > --- /dev/null
> > +++ b/urcu-qsbr-map.h
> > @@ -0,0 +1,63 @@
> > +#ifndef _URCU_QSBR_MAP_H
> > +#define _URCU_QSBR_MAP_H
> > +
> > +/*
> > + * urcu-map.h
> > + *
> > + * Userspace RCU header -- name mapping to allow multiple flavors to be
> > + * used in the same executable.
> > + *
> > + * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> > + * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
> > + *
> > + * LGPL-compatible code should include this header with :
> > + *
> > + * #define _LGPL_SOURCE
> > + * #include <urcu.h>
> > + *
> > + * This library is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU Lesser General Public
> > + * License as published by the Free Software Foundation; either
> > + * version 2.1 of the License, or (at your option) any later version.
> > + *
> > + * This library is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * Lesser General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU Lesser General Public
> > + * License along with this library; if not, write to the Free Software
> > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> > + *
> > + * IBM's contributions to this file may be relicensed under LGPLv2 or later.
> > + */
> > +
> > +/* Mapping macros to allow multiple flavors in a single binary. */
> > +
> > +#define rcu_read_lock rcu_read_lock_qsbr
> > +#define _rcu_read_lock _rcu_read_lock_qsbr
> > +#define rcu_read_unlock rcu_read_unlock_qsbr
> > +#define _rcu_read_unlock _rcu_read_unlock_qsbr
> > +#define rcu_quiescent_state rcu_quiescent_state_qsbr
> > +#define _rcu_quiescent_state _rcu_quiescent_state_qsbr
> > +#define rcu_thread_offline rcu_thread_offline_qsbr
> > +#define rcu_thread_online rcu_thread_online_qsbr
> > +#define rcu_register_thread rcu_register_thread_qsbr
> > +#define rcu_unregister_thread rcu_unregister_thread_qsbr
> > +#define rcu_exit rcu_exit_qsbr
> > +#define synchronize_rcu synchronize_rcu_qsbr
> > +#define rcu_reader rcu_reader_qsbr
> > +#define rcu_gp_ctr rcu_gp_ctr_qsbr
> > +
> > +#define get_cpu_call_rcu_data get_cpu_call_rcu_data_qsbr
> > +#define get_call_rcu_thread get_call_rcu_thread_qsbr
> > +#define create_call_rcu_data create_call_rcu_data_qsbr
> > +#define set_cpu_call_rcu_data set_cpu_call_rcu_data_qsbr
> > +#define get_default_call_rcu_data get_default_call_rcu_data_qsbr
> > +#define get_call_rcu_data get_call_rcu_data_qsbr
> > +#define get_thread_call_rcu_data get_thread_call_rcu_data_qsbr
> > +#define set_thread_call_rcu_data set_thread_call_rcu_data_qsbr
> > +#define create_all_cpu_call_rcu_data create_all_cpu_call_rcu_data_qsbr
> > +#define call_rcu call_rcu_qsbr
> > +
> > +#endif /* _URCU_QSBR_MAP_H */
> > diff --git a/urcu-qsbr.c b/urcu-qsbr.c
> > index 69effd5..8dcad33 100644
> > --- a/urcu-qsbr.c
> > +++ b/urcu-qsbr.c
> > @@ -32,6 +32,8 @@
> > #include <errno.h>
> > #include <poll.h>
> >
> > +#include "urcu-qsbr-map.h"
> > +
> > #define BUILD_QSBR_LIB
> > #include "urcu-qsbr-static.h"
> > /* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
> > @@ -121,10 +123,11 @@ static void update_counter_and_wait(void)
> > #endif /* !(CAA_BITS_PER_LONG < 64) */
> >
> > /*
> > - * Must commit rcu_gp_ctr update to memory before waiting for quiescent
> > - * state. Failure to do so could result in the writer waiting forever
> > - * while new readers are always accessing data (no progress). Enforce
> > - * compiler-order of store to rcu_gp_ctr before load rcu_reader ctr.
> > + * Must commit rcu_gp_ctr update to memory before waiting for
> > + * quiescent state. Failure to do so could result in the writer
> > + * waiting forever while new readers are always accessing data
> > + * (no progress). Enforce compiler-order of store to rcu_gp_ctr
> > + * before load rcu_reader ctr.
> > */
> > cmm_barrier();
> >
> > @@ -194,8 +197,8 @@ void synchronize_rcu(void)
> >
> > /*
> > * Mark the writer thread offline to make sure we don't wait for
> > - * our own quiescent state. This allows using synchronize_rcu() in
> > - * threads registered as readers.
> > + * our own quiescent state. This allows using synchronize_rcu()
> > + * in threads registered as readers.
> > */
> > if (was_online)
> > CMM_STORE_SHARED(rcu_reader.ctr, 0);
> > @@ -212,10 +215,11 @@ void synchronize_rcu(void)
> >
> > /*
> > * Must finish waiting for quiescent state for parity 0 before
> > - * committing next rcu_gp_ctr update to memory. Failure to do so could
> > - * result in the writer waiting forever while new readers are always
> > - * accessing data (no progress). Enforce compiler-order of load
> > - * rcu_reader ctr before store to rcu_gp_ctr.
> > + * committing next rcu_gp_ctr update to memory. Failure to
> > + * do so could result in the writer waiting forever while new
> > + * readers are always accessing data (no progress). Enforce
> > + * compiler-order of load rcu_reader ctr before store to
> > + * rcu_gp_ctr.
> > */
> > cmm_barrier();
> >
> > @@ -238,7 +242,8 @@ out:
> > * freed.
> > */
> > if (was_online)
> > - _CMM_STORE_SHARED(rcu_reader.ctr, CMM_LOAD_SHARED(rcu_gp_ctr));
> > + _CMM_STORE_SHARED(rcu_reader.ctr,
> > + CMM_LOAD_SHARED(rcu_gp_ctr));
> > cmm_smp_mb();
> > }
> > #else /* !(CAA_BITS_PER_LONG < 64) */
> > @@ -250,8 +255,8 @@ void synchronize_rcu(void)
> >
> > /*
> > * Mark the writer thread offline to make sure we don't wait for
> > - * our own quiescent state. This allows using synchronize_rcu() in
> > - * threads registered as readers.
> > + * our own quiescent state. This allows using synchronize_rcu()
> > + * in threads registered as readers.
> > */
> > cmm_smp_mb();
> > if (was_online)
> > @@ -265,7 +270,8 @@ out:
> > mutex_unlock(&rcu_gp_lock);
> >
> > if (was_online)
> > - _CMM_STORE_SHARED(rcu_reader.ctr, CMM_LOAD_SHARED(rcu_gp_ctr));
> > + _CMM_STORE_SHARED(rcu_reader.ctr,
> > + CMM_LOAD_SHARED(rcu_gp_ctr));
> > cmm_smp_mb();
> > }
> > #endif /* !(CAA_BITS_PER_LONG < 64) */
> > @@ -326,3 +332,5 @@ void rcu_exit(void)
> > {
> > assert(cds_list_empty(®istry));
> > }
> > +
> > +#include "urcu-call-rcu-impl.h"
> > diff --git a/urcu-qsbr.h b/urcu-qsbr.h
> > index 116fd77..984d70c 100644
> > --- a/urcu-qsbr.h
> > +++ b/urcu-qsbr.h
> > @@ -40,6 +40,8 @@
> > extern "C" {
> > #endif
> >
> > +#include "urcu-qsbr-map.h"
> > +
> > /*
> > * Important !
> > *
> > @@ -62,15 +64,15 @@ extern "C" {
> > * rcu_read_unlock()
> > *
> > * Mark the beginning and end of a read-side critical section.
> > - * DON'T FORGET TO USE rcu_register_thread/rcu_unregister_thread() FOR EACH
> > - * THREAD WITH READ-SIDE CRITICAL SECTION.
> > + * DON'T FORGET TO USE rcu_register_thread/rcu_unregister_thread()
> > + * FOR EACH THREAD WITH READ-SIDE CRITICAL SECTION.
> > */
> > -#define rcu_read_lock() _rcu_read_lock()
> > -#define rcu_read_unlock() _rcu_read_unlock()
> > +#define rcu_read_lock_qsbr() _rcu_read_lock()
> > +#define rcu_read_unlock_qsbr() _rcu_read_unlock()
> >
> > -#define rcu_quiescent_state() _rcu_quiescent_state()
> > -#define rcu_thread_offline() _rcu_thread_offline()
> > -#define rcu_thread_online() _rcu_thread_online()
> > +#define rcu_quiescent_state_qsbr() _rcu_quiescent_state()
> > +#define rcu_thread_offline_qsbr() _rcu_thread_offline()
> > +#define rcu_thread_online_qsbr() _rcu_thread_online()
> >
> > #else /* !_LGPL_SOURCE */
> >
> > @@ -122,4 +124,6 @@ extern void rcu_unregister_thread(void);
> > }
> > #endif
> >
> > +#include "urcu-call-rcu.h"
> > +
> > #endif /* _URCU_QSBR_H */
> > diff --git a/urcu.c b/urcu.c
> > index e529ac0..4ee9e3b 100644
> > --- a/urcu.c
> > +++ b/urcu.c
> > @@ -33,6 +33,8 @@
> > #include <errno.h>
> > #include <poll.h>
> >
> > +#include "urcu-map.h"
> > +
> > #include "urcu-static.h"
> > /* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
> > #include "urcu.h"
> > @@ -428,4 +430,7 @@ void rcu_exit(void)
> > assert(act.sa_sigaction == sigrcu_handler);
> > assert(cds_list_empty(®istry));
> > }
> > +
> > #endif /* #ifdef RCU_SIGNAL */
> > +
> > +#include "urcu-call-rcu-impl.h"
> > diff --git a/urcu.h b/urcu.h
> > index c6c54e7..00d9b75 100644
> > --- a/urcu.h
> > +++ b/urcu.h
> > @@ -43,12 +43,14 @@
> > extern "C" {
> > #endif
> >
> > +#include "urcu-map.h"
> > +
> > /*
> > * Important !
> > *
> > * Each thread containing read-side critical sections must be registered
> > - * with rcu_register_thread() before calling rcu_read_lock().
> > - * rcu_unregister_thread() should be called before the thread exits.
> > + * with rcu_register_thread_mb() before calling rcu_read_lock_mb().
> > + * rcu_unregister_thread_mb() should be called before the thread exits.
> > */
> >
> > #ifdef _LGPL_SOURCE
> > @@ -68,8 +70,16 @@ extern "C" {
> > * DON'T FORGET TO USE RCU_REGISTER/UNREGISTER_THREAD() FOR EACH THREAD WITH
> > * READ-SIDE CRITICAL SECTION.
> > */
> > -#define rcu_read_lock() _rcu_read_lock()
> > -#define rcu_read_unlock() _rcu_read_unlock()
> > +#ifdef RCU_MEMBARRIER
> > +#define rcu_read_lock_memb() _rcu_read_lock()
> > +#define rcu_read_unlock_memb() _rcu_read_unlock()
> > +#elif defined(RCU_SIGNAL)
> > +#define rcu_read_lock_sig() _rcu_read_lock()
> > +#define rcu_read_unlock_sig() _rcu_read_unlock()
> > +#elif defined(RCU_MB)
> > +#define rcu_read_lock_mb() _rcu_read_lock()
> > +#define rcu_read_unlock_mb() _rcu_read_unlock()
> > +#endif
> >
> > #else /* !_LGPL_SOURCE */
> >
> > @@ -100,4 +110,6 @@ extern void rcu_init(void);
> > }
> > #endif
> >
> > +#include "urcu-call-rcu.h"
> > +
> > #endif /* _URCU_H */
> > --
> > 1.7.3.2
> >
>
> --
> Mathieu Desnoyers
> Operating System Efficiency R&D Consultant
> EfficiOS Inc.
> http://www.efficios.com
>
> _______________________________________________
> rp mailing list
> rp at svcs.cs.pdx.edu
> http://svcs.cs.pdx.edu/mailman/listinfo/rp
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